Down to the Wire

While most eyes had been focused on Gemini 2 at
Cape Kennedy, work on still-to-be-resolved development problems continued
elsewhere. Two spacecraft systems indispensable for Gemini's first manned
mission - thrusters and ejection seats - remained question marks through most of
1964, and a third - fuel cells - though not slated for Gemini 3, was as yet
unqualified. What may have been the largest question of all centered on the
Gemini Agena, which throughout 1964 fell further behind schedule.

In April 1964, Rocketdyne seemed at last to have solved its major problems in
developing workable thrusters for Gemini, but misgivings persisted. When the Jet
Propulsion Laboratory approached Rocketdyne about developing a small engine for
the Surveyor spacecraft, Mathews protested. [210] He argued that the company was
still a year away from having the Gemini orbital attitude and maneuvering system
and reentry control system on a sound footing, and that the main reason the work
had improved was the belief that it would get no more NASA small-engine
contracts until Gemini work was almost done. Workloads in the California plant
were heavy, as shown by the large demands for overtime, and the original
$30-million contract had ballooned to over $74 million, of which almost $36
million was an overrun.

Despite the enormous infusion of effort and money, Rocketdyne had failed to
maintain schedules and deliveries. Engines for Spacecraft 2, for example, due in
February 1963, arrived on in January 1964, and "the delivered products leave
much to be desired." Mathews thought it "quite evident that all three interested
parties, the Gemini Program Office, the Surveyor Program, and Rocketdyne, will
benefit through the selection of a vendor other than Rocketdyne," since the
added work could only hamper Gemini without contributing much to Surveyor.45

This concern was echoed by manned space flight chief George Mueller;*
in a memorandum to his counterpart in the Office of Space Sciences, which had
charge of the Surveyor program, he urged that Rocketdyne be denied the contract.
MSC Director Gilruth also acted, setting up a special committee to survey
Rocketdyne's Gemini program. After hearing some harsh committee findings on 5
August 1964, Rocketdyne's president promised that whatever NASA wanted would be
done. Gilruth sent him a long list of recommendations a week later. Some changes
were already under way even while the committee was meeting, and more followed,
including a reorganization of Rocketdyne's Space Engine Division.46

Among the recommendations was a full-scale NASA audit of Rocketdyne's
business management practices and Space Engine Division operations. It was a
large undertaking, and a report was not ready until April 1965. Its findings
revealed a badly managed program. Having "grossly underestimated the magnitude
and complexities" of its Gemini subcontract, Rocketdyne had been slow to set up
a sound organization. As a result, budgets were poorly controlled "and
operations were inefficient," producing "significant cost overruns and delays."
Not only had outright overruns very nearly doubled the cost of the program, but,
of the 358 engines that should have been delivered by November 1964 under the
original contract terms, only 167 had actually been received. Frequent personnel
changes at top levels reflected the [211] program's weak management, as did the
company's complete inability to provide records showing the reasons for
technical problems, what action they prompted, or what impact each problem had
on costs and deliveries. The auditors recommended "that Rocketdyne's fee under
the Gemini subcontract be adjusted."47

When this report was released in the spring of 1965, the worst was already
over. Rocketdyne's performance had, in fact, begun to improve markedly in
mid-1964, although as late as October Gilruth still thought an alternative
source for thrusters might be a good idea. McDonnell received the first
long-duration attitude maneuvering thrusters in October 1964, just five months
after the new design had been released to production. By the time the audit
report was issued, both the attitude and reentry control systems had been fully
qualified in their Spacecraft 3 version. How greatly things had changed was
shown most clearly when the long-life thrusters, not expected to be ready before
Spacecraft 5, were actually installed in Spacecraft 4.48

Qualification of the Gemini escape system, like that of the spacecraft rocket
systems, was essential before astronauts could be committed to a mission. Rapid
progress early in 1964, which saw the development test program concluded,
augured well, as did a good start on dynamic proof-testing. A preliminary
sled-ejection test on 4 June 1964, to see if hatches and hatch actuators
functioned properly under abort conditions, went off without a hitch.
Qualification testing began on 1 July with a sled run to simulate conditions of
maximum dynamic pressure after an abort during the powered phase of launch
vehicle flight. Once again, everything worked.49

The same problem that had delayed development testing, one that had little to
do with seat design, again brought the test program to a halt. Some of the
pyrotechnic devices on which escape-system operation depended failed to arrive.
The result was a four-month gap after the July run. In the meantime, NASA had
decided to go ahead with a new test series. Sled and tower tests had been the
only dynamic simulations planned for the system. Neither, however, could show
the system working through its entire sequence as in a high-altitude abort. That
became the purpose of a plan to eject the system from a high-flying F-106,
worked out at a meeting between NASA, McDonnell, Weber Aircraft (the maker of
the system), and the 6511th Test Group at El Centro, California, on 12 June. The
first test, intended merely to show that the seat would work with the airplane,
was set for September with the F-106 on the ground. Two flights, using
production escape systems, were to follow, with the whole series to be finished
in a month. Once again, however, lack of pyrotechnics caused delays.
Enterprising engineers borrowed some from the ejection seat in North American's
paraglider tow test vehicle, enabling them to run the ground test on 15 October.
But nothing more could be done for three months.50

[212] Enough pyrotechnics were on hand for another sled run on 5 November,
which revealed a flaw in seat design. An instant after it had been ejected, one
of the seats suffered a structural failure of its armrest and side panel that
stopped the separation and recovery sequence. Seat and dummy smashed into the
ground, strewing wreckage for 140 meters along the track. The hard question now
was whether or not the test program had to be revised. The answer was no,
provided the reworked seat structure performed well in a test approximating the
most severe conditions for which the system was designed. In a sled run on 11
December, it did just that. The system came through with flying colors, bringing
that part of the qualification program to an end.51

It was perhaps just as well that Gemini 2 had been so long delayed. By
the end of 1964, only one of the four major parts of escape-system qualification
had been completed. Still to be conducted were simulated off-the-pad ejection
(Sope), personnel parachute, and high altitude ejection tests. All three resumed
in January 1965, when pyrotechnics at last began to arrive.

[213] First to get under way, on 11 January, was parachute testing. Four
dummy drops and 12 live jumps from low altitudes over the next month turned up
only minor problems. High-altitude testing followed.52
In the meantime, On 16 January (a year and a half after Sope development tests
ended) Sope qualification testing began. Shortage of pyrotechnics had again been
the chief culprit in the delay. The first try failed. One seat worked, but the
catapult on the right-hand seat fired too soon and exploded when the seat jammed
against the still partly closed hatch. Almost a month passed while all hatch
actuators were modified and the results checked out. Both the redesigned
actuators and the escape system proved themselves in flawless Sope tests on 12
February and 6 March.53

High-altitude ejection was the last test program to resume but the first to
finish. Nothing went wrong in the first test, an ejection at 4,780 meters at
mach 0.65 on 28 January. Two weeks later, however, in a test at 12,000 meters at
mach 1.7, the aneroid device that was supposed to trigger parachute deployment
failed, although everything else worked. That device also failed to deploy the
ballute on 17 February, in the first high-altitude live jump, forcing McDonnell
and Weber engineers to redesign the aneroid-controlled firing mechanism.
Although the aircraft ejection test did not have to be repeated, since being
ejected from the F-106 did not cause the failure, the parachute test program did
have to be revised. That meant an extra 10 dummy drops and 5 live jumps, which
began on 2 March. The final jump, on 13 March, qualified the personnel parachute
system and completed the qualification of the Gemini escape system as a whole.54
And not a moment too soon. The launch of the third Gemini mission, the first to
carry a human cargo, was only days away.

The demand for fuel cells was not so pressing in late 1964 as for thrusters
and ejection seats, since Spacecraft 3 and 4 were already being converted to
battery power as a result of earlier problems. GE's redesigned fuel cell, the
P3, had not at first lived up to its promise. Test sections performed
erratically, their outputs tending to decay under load and their lives falling
far short of requirements. This prompted NASA Headquarters to ask GPO on 10 July
to provide a backup battery-power module in case fuel cells were not ready for
the fifth Gemini mission. This was a drastic step, since Gemini 5 was slated for
seven days; a battery installation to handle so long a mission meant a severe
weight penalty and a narrow limit on what might be achieved during the flight.
One of the main reasons for putting fuel cells in Gemini had been to ease
constraints on such lengthy missions. GPO directed McDonnell to work out with
Eagle-Picher, the battery subcontractor, a plan for a backup system.55

Early in August, GPO enlarged the scope of the study, asking McDonnell to
cover the effects of substituting batteries for fuel cells in [214] all two-day
rendezvous missions, of using Agena-supplied power in a combined long-duration
and rendezvous mission, and of such changes on the fuel-cell program itself.
McDonnell found the feat possible but costly, especially in weight. At a meeting
on 14 August, Mathews and Burke decided to provide Spacecraft 5 with a combined
system of batteries for the peak loads and fuel cells for basic power needs. If
most of the experiments planned for the mission were discarded, Spacecraft 5
would only weigh 30 kilograms more with its battery-augmented system. NASA
Headquarters sanctioned the change on 1 October.56

The combined system reflected GE's success, finally, in pinpointing the
sources of fuel-cell shortcomings. GE engineers found that the life of test
stacks declined as electrical load and the temperature of reactants rose. The
greater the load - the amperage drawn from the stack - or the higher the inlet
temperature, the shorter the stack's life. With a constant load, a change of
only 17 kelvins (30°F) in reactant temperature - 313 kelvins (103°F) instead of
330 kelvins (133°F) - more than doubled stack life, from 125 to 290 hours.
Holding the temperature constant and varying the load produced similar results.
With batteries to handle peak loads, a major factor in truncated fuel-cell life
might have been countered.57

These findings were based only on analysis of prior test data. Now GE revised
its test program to see what effect lowered inlet temperatures and reduced loads
actually had on test stacks. The results confirmed the premise. Two test units
under a steady three-ampere load with reactants at 297 kelvins (75°F) lasted
1,100 and 800 hours. Further tests produced equally encouraging results at
various levels of load and temperature under normal and abnormal conditions. All
difficulties were not yet out of the way, but those that remained were largely
matters of detail.58

Concern about "the rapidly rising costs of the General Electric fuel cell
development program, coupled with the lagging development," persisted for a
while; but, significantly, that worry was expressed in a memorandum never
sent.59
The Gemini Program Office in Houston retained some doubts about fuel-cell
prospects through the early fall of 1964, urging NASA Headquarters to allow
batteries to replace fuel cells in Spacecraft 6 to ensure meeting the prime
objective of that mission, rendezvous with an Agena target vehicle. Headquarters
demurred until 6 November, but then granted the change.60

That decision stood, Spacecraft 6 eventually flying with battery power. In
the meantime, however, the response of fuel-cell test units to lower
temperatures was so marked during late summer and early fall as to convince both
NASA and its contractors that the power system for Spacecraft 5 need not be
augmented by batteries. That change was therefore canceled on 18 December 1964.
[215] The Gemini fuel cell completed its basic qualification test program in May
1965, three months before it flew in the fifth Gemini mission.61

Agena was still further down the line, and its lagging pace showed no signs
of speeding up during 1964. Project Gemini received its first Agena D at the end
of April 1964, but nearly five months passed before it was converted into
GATV-5001, the first Gemini Agena Target Vehicle. Lockheed completed that effort
on 24 September and transferred the vehicle to the systems test complex, where
cabling it up for preliminary vehicle systems tests began the next day. Not too
surprisingly, testing did not run smoothly.

The hardest and most stubborn problems centered in Agena's command and
communication (C&C) system - the electronic devices for tracking the
vehicle, monitoring its subsystems, and passing commands to the vehicle in
orbit. Because of Gemini's unique demand for rendezvous and docking, Lockheed
had to design and prove a new C&C system for the Gemini Agena. The new
design struck GPO as very good, a judgment confirmed by a special consultant
group from Stanford Research Institute, which recommended only minor changes.
During testing in October, however, parts of the system started acting up.
Troubleshooting got GATV-5001 through its testing, but it seemed all too likely
that the C&C system suffered from basic defects in its mechanical and
electronic design. The question became, as Mathews later recalled, "Should we
live with what we had, or should we back off and completely redesign the
configuration?" When the problems persisted, the Air Force insisted on redesign,
and Lockheed finally initiated a "Ten Point Plan for C&C Equipment" in
February 1965.62

In the meantime, GATV-5001 had emerged from its preliminary tests in November
1964 and gone to Lockheed's Santa Cruz Test Base for a round of captive-firing
tests. First, however, the target docking adapter had to be installed. This was
the unit, built by McDonnell but carried aloft by Lockheed's Agena, to which the
spacecraft would attach. When Lockheed workers hoisted the adapter into the test
stand and tried to mate it with the Agena, they found it did not fit. After some
struggling, they managed to get the two physically hooked together, but the
wiring failed to match. The captive firing had to be postponed until January.63

The test on 20 January 1965 simulated a full two-week mission. It included
related firings of both primary and secondary propulsion systems, with
operational data transmitted to telemetry stations at the test site and at
Lockheed's Sunnyvale plant. The propulsion systems worked well, but the C&C
system again had problems. One part, the programmer time accumulator, jumped
erratically, picking up almost eight extra weeks. Shipped back to Sunnyvale on 1
February, GATV-5001 lost three weeks while Lockheed tried to fix the capricious
timer. [216] A makeshift fix allowed GATV-5001 to move on to the next phase,
electromagnetic and radio-frequency interference tests, while engineers
continued their efforts to diagnose and cure the jumping timer. By 23 February,
when the interference tests began, GATV-5001 was more than a month behind
schedule.64

Interference tests ended 9 March, but the vehicle stayed in the anechoic
chamber for another week while Lockheed checked out its answer to the erratic
timer and to a telemetry synchronization problem that had also cropped up. On 18
March, GATV-5001 moved to the systems test complex for a planned six days of
"minor" modifications: filters were to be installed in the command controller
(another part of the C&C system) and the forward auxiliary rack (which
supported the target docking adapter and housed most of the C&C gear) was to
be aligned. These two tasks proved to be more than minor. The first eventually
required a complete redesign, the second extensive machining. The result was
another lost month. By the end of March, GATV-5001 was 66 days behind
schedule.65

Final systems testing got under way on 9 April and ended with a simulated
flight on 6 May. On 27 May, the Air Force and Aerospace team found GATV-5001
formally unacceptable for Gemini, since FACI (first article configuration
inspection) from 10 to 26 May had shown that it was not flightworthy. SSD took
the vehicle anyway, but conditionally. Lockheed was expected to correct all
defects; some were merely matters of paperwork, but others, like propulsion and
C&C systems qualification, were major efforts. GATV-5001 was then flown to
the Cape on 29 May, to be used as a development test vehicle.66

In the meantime, the first Atlas booster for Gemini had joined the program on
1 December in San Diego. It had then been shipped by truck to Cape Kennedy, a
six-day trip. It was erected on complex 14 a week later, to help in checking out
the launch pad and ground support equipment. Finished with that by 11 February,
the Atlas was moved to a hangar, there to be modified and stored until GATV-5002
arrived.67

* Mueller, of course, had an additional concern that
did not affect Mathews: Rocketdyne was also the contractor for the Apollo
thrusters and was a competitor with Space Technology Laboratories, Inc. (STL)
for the lunar module descent engine. In January 1965, STL was awarded the
development and production contract.